1. Field of the Invention
The present invention relates to a lithography system and a lithography method using the same. More particularly, it relates to a lithography system and a lithography method that can accelerate processing of main deflector data in beam positioning.
2. Description of the Related Art
As the semiconductor circuits have become smaller and more highly integrated, a charged particle beam lithography system has increasingly been used instead of conventional photolithography system. The charged particle beam lithography system draws a pattern on a mask using a charged particle beam such as an electron beam.
In order to accelerate the drawing speed in electron beam patterning technologies, various technologies have been proposed, and they are now used in real systems. For example, a mode called “variable beam shape mode” is used. In this mode, a variable-shape beam having variable beam shapes may be projected according to a pattern shape to be formed, by overlapping first and second rectangle apertures. Thereby, as compared with the case where a circular beam is used, the number of exposure can be lowered greatly.
Moreover, a mode called “a continuous stage moving mode” is employed as a mode that improves a drawing speed by shortening the stage moving time. This mode draws each frame, by dividing a pattern to be drawn on a sample (a mask) into a strip-shaped “frame areas” and continuously moving the stage.
Moreover, “a vector scan mode” has been proposed as a deflection mode of an electron beam. A vector scan mode further divides a “frame area” into small areas called “sub-field areas”, and the sub-field area is patterned by deflecting a variable shaped beam to its required part only (for instance, see JP H01-152726 A).
This mode employs two deflectors: a main deflector; and a auxiliary deflector. The main deflector serves for positioning a beam to one sub-field area. The auxiliary deflector serves for patterning in a sub-field area.
In a conventional lithography system using this mode, a time for processing auxiliary deflector data is longer than that for processing main deflector data. Therefore, a problem to be solved was to shorten the processing time of the auxiliary deflector data for shortening the patterning time.
However, since downsizing of the sub-field area is in progress recently, the number of the sub-field areas is increasing. For this reason, a processing time of the main deflector data is increasing, and a processing time of auxiliary deflector data is decreasing. Therefore, it is becoming eminent that the processing time for main deflector data affects the stage moving speed, and the throughput of the lithography system tends to become lower.